Fix dateutil version

Author: akariv

setup.py

@@ -40,6 +40,7 @@ def read(*paths):
     'tabulator>=1.17.0',
     'globster>=0.1.0',
     'dataflows>=0.0.57',
+    'python-dateutil<2.8.1',
 ]
 SPEEDUP_REQUIRES = [
     'dataflows[speedup]',